Anastomosis punch device and method

ABSTRACT

An anastomosis punch device, and method of using same, for creating a circular hole in the aortic wall, where the device also segregates the hole from the blood flow path such that no blood is lost through the hole during attachment of the vein graft. The invention is a hand-held punch comprising an elongated housing to be gripped by the surgeon, the housing retaining in a coaxially aligned manner a distally extended punch head and cutting disk mounted onto a shaft, a cutting sleeve having a distal cutting rim which cuts a circular plug in cooperation with the punch head, an umbrella-like flexible dam formed of an elastic material and adjoined to the punch shaft adjacent said punch head in a manner which allows it to be deployed radially outward with the enlarged open rim facing the proximal direction, and a deployment ram movable axially relative to the dam to spread open the dam.

BACKGROUND OF THE INVENTION

This invention is a medical device and relates generally to the field ofpunch devices used in performing anastomosis (the joining of a hollow ortubular organ to another hollow or tubular organ), and in particularsuch devices used in the surgical joining of a vein graft to the aorticwall, where the punch device is used to create the hole in the aorticwall.

In coronary bypass surgery, a blocked segment of the coronary artery isbypassed by attaching a vein graft to the aorta above the blocked pointand to the artery downstream of the blocked point, such that blood flowis routed around the blockage through the vein graft. In a commontechnique used to attach the graft, a hole is created in the aortic wallby first creating a small slit using a scalpel. The cutting disk of apunch device is then inserted through the slit. The cutting disk ismounted onto a thin shaft, which is coaxially received by a tubularsleeve member, the end of which is provided with an annular cutting edgeor rim. With the aortic wall between the disk and the sleeve, either thedisk is retracted into the sleeve or the sleeve is advanced beyond thedisk. This operation cuts a circular opening in the aortic wall, and theplug cut from the wall is entrapped within the, sleeve and disk. Thepunch device is then removed and the surgeon proceeds with theanastomotic procedure.

It is necessary to temporarily occlude the opening in the aortic wall insome manner after removal of the plug to prevent excessive loss of bloodduring the anastomotic procedure. The most commonly employed method isto apply a C-shaped surgical clamp to the side of the aortic wall at theproposed site of the anastomosis prior to cutting the aorta andintroducing the punch. The clamp compresses only a portion of the aorta,allowing continued blood flow past the clamped area. This technique canbe problematic in that application of the clamp may cause damage to theaorta or release plaque fragments or atheromatous debris into the bloodstream when the clamp is released.

One alternative technique for blocking blood flow through the holecreated in the aortic wall by a combination punch device is shown inU.S. Pat. No. 5,944,730 of Nobles et al. The Nobles et al. device, asdescribed in the second embodiment of the disclosure, is a grosslyelongated instrument having an occluding inverting member mounted ontothe distal end of a long, slender flexible tube, an inverter handleassembly, and an intermediately disposed punch assembly. The punchassembly is joined to the inverter handle assembly in a disconnectablefashion, such that the punch assembly is detached from the inverterhandle assembly and slid distally along the flexible tube to remove theplug from the aortic wall, after which it is translated proximally andrejoined to the inverter handle assembly. The inverter handle assemblyis then manipulated to cause the inverting member to fold onto itselfinto a conical configuration and the entire device is pulled in theproximal direction to seal the aortic wall. Each end of the invertingmember must be attached to a different elongated tubular member whichare slidably movable in the axial direction relative to each other. Theprovision of separable punch and inverter handle assemblies, theelongated flexible tube on which is mounted the occluding member, andthe overly complicated design of the occluding member results in anawkward instrument of excessive length which is difficult to operate inan efficient and straightforward manner. Additionally, there is nostructure to block blood flow through the hole in the aortic wall duringthe time period while the punch assembly is being withdrawn and rejoinedto the inverter handle assembly prior to expansion of the invertingmember and retraction of the apparatus.

It is an object of this invention to provide an anastomosis punch devicefor creating a hole in the aortic wall, and method of use for same,which has an occluding structure to prevent blood from exiting the holecreated in the aortic wall during attachment of the vein graft, wherethe device comprises an elastic dam membrane having circumferentiallyspaced longitudinal ribs, where the ribs may be spread to open themembrane into a conical configuration in an umbrella-like manner tosurround the hole, then collapsed for withdrawal after the vein has beenpartially secured, where the dam is affixed to the shaft of the punchassembly distal to the annular cutting disk and the cutting sleeve,where the cutting sleeve blocks blood flow through the hole created inthe aortic hole prior to expansion of the elastic dam membrane, suchthat the punch device is a compact instrument which is easilymanipulated by the surgeon.

SUMMARY OF THE INVENTION

The invention comprises an anastomosis punch device, and method of usingsame, for creating a circular hole in the aortic wall, where the devicealso segregates the hole from the blood flow path such that no blood islost through the hole during attachment of the vein graft. The inventionis a compact hand-held punch comprising an elongated housing to begripped by the surgeon, the housing retaining in a coaxially alignedmanner a cutting disk, a cutting sleeve having a distal cutting rimwhich cuts a circular plug in cooperation with the cutting disk, anexpandable, umbrella-like, flexible dam formed of an elastic tubularmaterial and adjoined to the shaft of the punch assembly distally to thecutting disk and cutting sleeve in a manner which allows it to bedeployed radially outward with the enlarged open rim facing the proximaldirection, and a deployment ram movable axially relative to the dam tospread open the dam. The surgeon inserts the punch head, the elastic damand cutting disk through the aortic wall, then advances the cuttingsleeve against and over the cutting disk to remove a circular plug ofaortic wall, with the plug being retained within a chamber defined bythe cutting sleeve and the cutting disk and the cutting sleeve locked inthe advanced position. The ram is then advanced relative to the dam,causing the proximal end of the dam to spread outwardly to form a coneshape, and the ram is locked in position. The rim of the expanded dam isthen drawn against the interior wall of the aorta, thus forming aconical dam about the hole. The vein graft is then attached to theaortic wall at the hole using known suturing techniques while the deviceremains in place. Once the vein is sufficiently attached to the aorticwall in loose manner, the ram is retracted relative to the dam, allowingthe dam to collapse into the passive configuration with minimal diameterbecause of the elastic nature of the membrane. The entire device is thenwithdrawn between the sutures and completely out of the aorta, with thesutures then quickly tightened to connect the vein graft to the aorta.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external side view of the device.

FIG. 2 is a cross-sectional view showing the punch head, elastic damassembly and cutting disk of the device as inserted into the aorticwall, taken along line 11—11 of FIG. 1.

FIG. 3 is a cross-sectional view similar to FIG. 2, showing the plugremoved from the aortic wall.

FIG. 4 is a partial cross-sectional view similar to FIG. 3, showing theram advanced and the dam deployed against the aortic wall.

FIG. 5 is a partial view of the device similar to FIG. 4, showing theram advanced and the dam deployed against the aortic wall.

FIG. 6 is a partial, exposed view of the device showing the ramdeployment assembly.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawings, the invention will now be described indetail with regard for the best mode and the preferred embodiment.

As shown generally in FIG. 1, the invention is an anastomosis punchdevice comprising a generally elongated, tubular instrument housing 10,a punch assembly 30, a cutting sleeve assembly 50, an elastic damassembly 70 and a deployment ram assembly 90. The device is configuredas an integral apparatus of compact design so as to be easily grippedand manipulated by surgeon. For example, a device having a housing 10approximately 9 cm in length and approximately 8 mm in diameter, withthe distal portion of the punch assembly 30 extending only about 4 cmfrom the distal end 12 of the housing 10, is representative of a verysuitable size. With reference also to FIG. 2, the elongated instrumenthousing 10 is shown to comprise a proximal end 11 and a distal end 12,where the distal end 12 is the end positioned against the aortic wall100 during use. For purposes of this disclosure, references to thedistal direction or a distal element shall mean the direction or elementtoward the aortic wall 100 with the device in use, while references tothe proximal direction shall means the opposite direction, i.e.,external to away from the aortic wall 100. A pair of laterally extendingfinger grips 18 are externally mounted on the instrument housing 10,preferably approximately 4 cm from the proximal end 11 of the instrumenthousing 10 . A first coaxial cylindrical bore 13 extends from theproximal end 11 within the body of instrument housing 10 to the distalend 12. Cutting sleeve locking means 20, comprising as shown atransverse bore 15 extending into the first bore 13, is provided nearthe proximal end 11 to receive a sleeve locking pin 16, which is used tosecure the cutting sleeve assembly 50 in the advanced position relativeto the instrument housing 10, as shown in FIG. 3. Equivalentconstructions for cutting sleeve locking means 20 may be utilized aswell. A longitudinally extending sleeve guide slot or pair of slots 17is provided in first bore 13, the sleeve guide slot 17 receiving theguide tabs 59 mounted onto the tubular shaft 52 of the cutting sleeveassembly 50 to prevent rotation of the cutting sleeve assembly 50 withinthe instrument housing 10 to maintain proper alignment between thetransverse bore 15 and a pin receiving aperture 58 located in thetubular shaft 52. A longitudinally extending ram guide slot 19 isprovided adjacent or toward the distal end 12 of the instrument housing10 to provide a channel for controlled movement of the handle 94 of thedeployment ram assembly 90 in either axial direction.

Means 60 to create a circular opening 103 in the aortic wall 100comprise in combination punch assembly 30 and cutting sleeve assembly50. Punch assembly 30 is mounted coaxially within instrument housing 10with a portion extending from the distal end 12 of the instrumenthousing 10. Punch assembly 30 comprises a punch head 31 mounted onto ashaft 33, with the shaft 33 fixed within the instrument housing 10 bydetent member 34. The punch head 31 is a conical or bladed member with asharp cutting edge or point such that relatively easy penetration can beattained through the aortic wall 100 by direct pressure on the exteriorside 102 of the aortic wall 100. An annular rim or disk member 32,preferably about 3 to 6 mm in diameter, is positioned intermediately onshaft 33 with the edge of the disk 32 having a relatively sharp lip.

The outer diameter of the disk 32 is sized to correspond to the internaldiameter of the annular cutting rim 55 and cutting sleeve 54 of thecutting sleeve assembly 50, the outer diameter of disk 32 being onlyslightly smaller than the internal diameter of cutting rim 55 andcutting sleeve 54, such that the cutting rim 55 and cutting sleeve 54can be advanced over the disk 32 to produce a cutting action to remove acircular plug 104 from the aortic wall 100, as shown in FIG. 3.

Cutting sleeve assembly 50 is coaxially positioned within instrumenthousing 10, fitting within first bore 13 such hat sliding movement ofthe cutting sleeve assembly 50 relative to the instrument housing 10 andpunch assembly 30 in the axial direction is possible. Cutting sleeveassembly 50 comprises a tubular shaft 52 which extends from both thedistal end 12 and the proximal end 11 of the instrument housing 10. Aflange handle or button 51 is mounted onto the proximal end of thetubular shaft 52, allowing the cutting sleeve assembly 50 to be advancedby pressure from the surgeon's thumb or palm A spring member 57 ismounted between the proximal end 11 of the instrument housing 10 and thebutton 51, and biases the cutting sleeve assembly 50 in the retractedproximal direction until sufficient pressure is applied to advance it inthe distal direction. The tubular shaft 52 defines a coaxial bore 53which snugly receives the shaft 33 of the punch assembly 30. A pinreceiving aperture 58 is positioned toward the proximal end of thetubular shaft 52, sized to receive sleeve locking pin 16 when the sleevecutting assembly 50 is advanced, as shown in FIG. 3. One or morelongitudinally extending guide tabs 59 are provided on the exterior oftubular shaft 52, the guide tabs 59 being received by sleeve guide slots17 to preclude relative rotation of the cutting sleeve assembly 50 andtho instrument housing 10. Longitudinal slots 61 are provided on thetubular shaft 52 to allow axial movement of the tubular shaft 52 pastthe punch detent member 34. A ram opening 62 extends along the distalportion of the tubular shaft 52 contained within the housing 10 andthrough a portion of the cutting sleeve 54 to allow passage of theparallel shafts 93 on the run assembly 90.

The distal end of the cutting sleeve assembly 50 comprises a tubularcutting sleeve 54 mounted onto the end of tubular shaft 52, the cuttingsleeve 54 extending radially outward to have both a larger internaldiameter than the internal diameter of bore 53, in order to define achamber 56 which receives the cutting disk 32 of the punch assembly 30,as well as the plug 104 which is removed from the aortic wall 100, andto have a larger external diameter than the external diameter of tubularshaft 52. The distal end of the cutting sleeve 54 is beveled orsharpened to provide an annular cutting rim 55. The size andconfiguration of the cutting rim 55 and sleeve 54 are such that whenthey are advanced against and over the punch disk 32, a shearing orcutting action is effected.

Affixed immediately to the proximal side of punch head 31 on the punchshaft 33 is the elastic dam assembly 70, the means for occluding bloodflow through the opening 103 in the aortic wall 100. Elastic damassembly 70 comprises a tubular elastic membrane or sheet material 72impermeable to blood, preferably formed of a polymeric material, whichin the passive, non-stretched state has a generally cylindrical or avery tight conical configuration of minimal diameter snugly encirclingthe shaft 33. The membrane 72 is mounted onto, is formed integrallywith, or encases a plurality of relatively rigid, generally linearstruts or rib members 73, generally aligned in the axial or longitudinaldirection and evenly spaced in the circumferential direction. The distalend 75 of the elastic membrane 72 is securely attached to or affixedaround the shaft 33 by fixation means or ring member 71, while theproximal end 76 of the membrane 72 is non-attached to any portion of thepunch assembly 30 and defines a sealing rim 74, which may be formed in abeaded or thickened configuration to provide a better seal against theinterior side 101 of the aortic wall 100. The membrane 72 is mountedsuch that it may be flared outwardly in an umbrella-like fashion into aconical active configuration by advancement of the deployment ramassembly 90 toward the fixed distal end 75 and against the ribs 73, withthe ribs 73 being pushed away from the shaft 33 at an acute angle tostretch, support and extend the elastic membrane 72, and with theexpanded sealing rim 74 thus presenting a relatively largecircumference, as shown in FIGS. 4 and 5. When the deployment ramassembly 90 is retracted to remove the pressure against the rib members73, the elasticity of the membrane 72 causes it to retract into thepassive cylindrical configuration of minimal diameter tightly encirclingthe shaft 33.

The means to deploy or expand the elastic membrane 72, deployment ramassembly 90, is mounted parallel with the punch shaft 33, and comprisesa pair of parallel shaft members or rods 93 connected at their proximalend by a semi-circular bridging member 98 to a transversely extendinghandle 94, which is positioned within ram guide slot 19 of instrumenthousing 10, such that the ram assembly 90 is movable in the axialdirection relative to the housing 10, as shown in FIG. 6. The distalportion of the deployment ram assembly 90 extends out of the instrumenthousing 10, the parallel shafts 93 extending through the proximal end ofthe cutting sleeve 54 and through apertures in the cutting disk 32. Theparallel shafts 93 connect to a beveled, curved or cone-shaped head ordistal end 91. The distal portion of the beveled head 91 fits within thesealing rim 74 of the elastic dam assembly 70 in its passive conditionwhen the deployment ram assembly 90 is advanced toward the fixation ring71, such that its movement in the distal direction results in it beingpositioned internally within the tubular elastic membrane 72 in order toeffect expansion of the membrane 72 as it is advanced. The outerdiameter and angle of the beveled head 91, as well as the distance oftravel relative to the dam assembly 70, is such that the membrane 72 issignificantly expanded when the ram assembly 90 is fully advanced, withthe sealing rim 74 presenting a relatively large circumference to abutthe internal side 101 of the aortic wall 100 sufficient distance fromthe hole 103 to provide room for the surgeon to apply the sutures. Meansto lock the deployment ram assembly 90 in the advanced position areprovided, and as shown comprises an annular locking collar 95 having ofcollar slot 96 of sufficient width to allow passage of the ram handle 94from one side to the other. The locking collar 95 is positioned in anannular collar channel 97 located on the instrument housing 10 such thatthe collar 96 may be rotated relative to the housing 10. With the collarslot 96 aligned with the ram guide slot 19, as shown in FIGS. 1, 2 and3, the ram assembly 90 may be advanced to the deployment position,whereupon the locking collar 95 is rotated such that the collar slot 96is no longer aligned with the ram guide slot 19 and the collar 95prevents movement of the ram assembly 90 in the proximal direction, asshown in FIGS. 4 and 5.

To create the hole 103 in the aortic wall 100 to perform anastomosis ofthe vein graft, the surgeon creates a small slit with a scalpel in theaortic wall 100 and introduces the punch head 31 of the device into theslit, or using the punch head 31 alone to penetrate the aortic wall 100,advances the instrument housing 10 such that the punch head 31, theelastic dam assembly 70 and the cutting disk 32 are positioned withinthe interior of the aortic wall 100, as shown in FIG. 2. The surgeonnext advances the cutting sleeve assembly 50 relative to the instrumenthousing 10 and the punch head assembly 30, thereby causing a circularplug 104 to be removed from the aortic wall 100 because of theinteraction between the annular cutting rim 55 and the punch disk 32.The cutting sleeve assembly 50 is then locked in the advanced position,as shown in FIG. 3, by inserting locking pin 16 into the pin receivingaperture 58 of the tubular shaft 52. By locking the cutting assembly 50in the advanced positioned, the combination of the punch head disk 32and the cutting sleeve 54 create a sealed chamber 56, such that theaortic plug 104 is retained therein and not released into the bloodstream. The deployment ram assembly 90 is then advanced relative to thedam assembly 70 and the punch assembly 30, and is locked in the advancedposition by rotating locking collar 95, as shown in FIGS. 4 and 5. Thiscauses expansion of the elastic membrane 72, the beveled head 91 of theram assembly 90 pressing radially outward against the rib members 73.With the membrane 72 in the open, conical configuration, the instrumenthousing 10 is slightly withdrawn, such that the sealing rim 74 of themembrane 72 seats firmly against the interior side 101 of the aorticwall 100. In this manner, blood within the aorta is prevented frompassing through the hole 103 in the aortic wall 100 while the vein graftis being sutured in place. The vein graft is loosely sutured in knownmanner with the device in place. Once the initial suturing is completed,the device is advanced slightly, the locking collar 95 is rotated toalign the collar slot 96 with the ram guide slot 19 to allow movement ofthe handle 94 in the proximal direction and the deployment ram assembly90 is retracted. With the beveled head 91 withdrawn, the elasticity ofthe membrane 72 causes it to resume its passive cylindrical shape (as inFIG. 3), its outer diameter being smaller than the diameter of the hole103. In this passive configuration, the entire device is then removedfrom the hole 103 in the aortic wall 100 and between the sutures, withthe surgeon quickly tightening the vein graft sutures to secure the veinagainst the aortic wall 100.

It is contemplated that equivalents and substitutions to certainelements set forth above may be obvious to those skilled in the art, andthe true scope and definition of the invention therefore is to be as setforth in the following claims.

I claim:
 1. An anastomosis punch device having means to create anopening in an aortic wall and means to block flow of blood through saidopening, the device comprising: a generally elongated, unitary, tubularhousing having a proximal end and a distal end; a punch assemblycomprising a shaft extending from said distal end of said housing, apunch head mounted on the distal end of said shaft, and a cutting diskfixedly mounted intermediately on said shaft, said punch assembly beingfixed relative to said housing; a cutting sleeve assembly comprising atubular shaft, a bore within said tubular shaft, a cutting sleevemounted onto said tubular shaft and a chamber defined by said cuttingsleeve, wherein the diameter of said cutting sleeve is greater than thediameter of said tubular shaft, wherein said cutting sleeve and saidchamber are disposed completely external to said housing and adjacentsaid distal end of said housing prior to initiation of a cuttingoperation, and wherein said tubular shaft extends through both saiddistal end and said proximal end of said housing, and where said cuttingsleeve is axially movable relative to said housing and said punchassembly; an elastic dam assembly affixed to said punch assembly,wherein said dam assembly comprises a tubular impermeable elasticmembrane and longitudinally extending rigid rib members supporting saidelastic membrane, wherein said elastic membrane has a distal endattached to said punch assembly and a non-attached proximal end defininga sealing rim, said elastic membrane having a generally cylindricalpassive configuration of minimal diameter and a generally conical activeexpanded configuration, and wherein said distal end of said elasticmembrane is affixed to said punch assembly shaft proximally adjacent tosaid punch head and said proximal end of said elastic membrane isdistally adjacent to said cutting disk when in said passiveconfiguration; a deployment ram assembly for expanding said elasticmembrane from said passive configuration to said active configuration,said deployment ram assembly comprising a parallel shaft external tosaid punch assembly shaft, a beveled head joined to said parallel shaft,and a handle connected to said parallel shaft and extending radiallyfrom said housing, said parallel shaft extending from said distal end ofsaid housing such that said beveled head is disposed distally adjacentsaid cutting disk and proximally adjacent said proximal end of saidelastic membrane prior to advancement of said deployment ram assemblyfor deployment of said elastic membrane, wherein said deployment ramassembly is axially movable relative to said housing, said bunchassembly and said elastic dam assembly, such that said beveled headadvances internally relative to said elastic membrane and pushesoutwardly against said rib members when advanced in the distal directionrelative to said elastic membrane.
 2. The device of claim 1, where saiddeployment ram assembly comprises a pair of parallel shafts.
 3. Thedevice of claim 2, where said deployment parallel shafts are positionedadjacent said punch assembly shaft and extend through said cuttingsleeve and said cutting disk.
 4. The device of claim 1, where said punchassembly shaft is positioned within said cutting sleeve assembly bore,and where said cutting disk is received within said chamber when saidcutting sleeve assembly is moved distally relative to said punchassembly.
 5. The device of claim 4, further comprising cutting sleevelocking means to lock said cutting sleeve assembly in position relativeto said housing and said punch assembly when said cutting sleeveassembly is moved distally relative to said punch assembly, such thatsaid cutting disk is positioned within said chamber.
 6. The device ofclaim 1, further comprising means to lock said deployment ram assemblyin position relative to said punch assembly and said elastic membranewhen said deployment ram assembly is moved distally relative to saidpunch assembly and said elastic membrane.
 7. The device of claim 6,wherein said means to lock said deployment ram assembly comprises arotatable annular collar mounted onto said housing, said collar having aslot sized to allow passage of said handle, wherein said handle can belocked on the distal side of said collar by rotating said collar aboutsaid housing.
 8. The device of claim 5, wherein said cutting sleevelocking means comprises in combination a transverse bore positioned insaid housing, a pin receiving aperture positioned in said cutting sleevetubular shaft, and a locking pin positioned within said transverse borewhich is adapted for insertion into said pin receiving aperture whensaid pin receiving aperture is aligned with said transverse bore byadvancing said cutting sleeve assembly distally relative to saidhousing.